Signal system.



1. P. BUCHANAN & F. B. WIEGAND.

SIGNAL SYSTEM. APPLICATION FILED MAY 6. 1910. RENEWED JUNE 28.1915.

1,150,494. Patented Aug. 17, 1915.

3 SHEET$SHEET I.

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J. P. BUCHANAN & F. B. WIEGAND.

SIGNAL SYSTEM.

APPLICATIOW FILED MAY 6.1 910. RENEWED JUNE 28.1915.

1,150,494. Patented Aug. 17,1915.

3 SHEETSSHEET 2.

Black No 3' W12 eases COLUMBIA PLANoGnAPn co..wAs1-uNGTON. D. c.

J. P. BUCHANAN & F. B. WIE'GAND.

SIGNAL SYSTEM.

APPLICATION man MAY 6, 1910. RENEWED JUNE 28,1915.

1,150,494. Patented Aug. 17, 1915.

3 SHEETS-SHEET 3.

l .4 l l I cOLufABu PLKNOGIAPH C0..WASHlNgTON. D. c.

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JOHN P. BUCHANAN AND FREDERIGK B. WIEGAND, OF CLEVELAND, OHIO.

SIGNAL SYSTEM.

Application filed May 6, 1910, Serial No. 559,701. Renewed June 28, 1915. Serial No. 36,907.

To all whom it may concern Be it known that we, JOHN P. BUCHANAN and FREDERICK B. WIEGAND, citizens of the United States, and residents of Cleveland, county of Cuyahoga, and State of Ohio, have jointly invented a new and useful Improvement in Signal Systems, of which the following is a specification, the principle of the invention being herein explained and the best mode in which we have contemplated applying that principle, so as to distinguish it from other inventions.

Our invention relating as indicated to signal systems, has regard more particularly to signal systems of the electric type wherein operation is automatically effected through the passing of a train by shunting an electric circuit.

The object of the invention is the provision of a signal system of the kind referred to, which will afford a maximum of safety by providing absolutely against an accidental indication of safety by any contrariety of current flow, as also render the system practically a wireless one.

Further objects include the provision of an improved relay construction in combination with such a system, whereby increased efliciency is obtained as well as positive op eration despite variation in the exciting cur rent.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings, Figure 1 represents in diagrammatic fashion a block signal apparatus wherein our several improvements have been incorporated; Fig. 2 is a similar view showing a slightly modified arrangement of apparatus; Fig. 3 is a side elevation of the improved construction of relay utilized in connection with our system; Fig. 4 is a plan view of such relay; Fig. 5 is a transverse section thereof taken on the line 55, Figs. 3 and 4; Figs. 6 and 7 are diagrams showing such relay under different operative conditions, and Figs. 8, 9 and 10 are respectively a side elevation, plan view, and section of a modified construction of such relay.

Description of such relay thus illustrated in two different specific forms may properly precede a description of the general system wherein it is here proposed to utilize the advantageous mode of operation of the relay. In the form of the latter illustrated in Figs. 3, 4: and 5, said relay A is composed of two coils or electro-magnets a a, which coils are connected in a closed magnetic circuit. The structure whereby such closure of the magnetic circuit set up by the coils in question is obtained, may obviously be various, but as shown, it includes simply two bars or back-straps a respectively connecting the corresponding ends of the cores (0 in the two coils, each such bar a being provided with a similarly directed projection or lug centrally between such cores. The arm a designed to be actuated by the relay is pivotally mounted adjacent to such projections or lugs being provided with an armature a extending transversely thereof, and in position to be drawn or pulled to said lugs upon proper excitation of the coils. Arm a is in turn used to efi'ect closure of one or the other of two circuits, by contacting with corresponding contact points a a between which its outer end plays.

By reason of the closure of the magnetic circuit through the cores and back straps of the relay, it will follow that the armature will be actuated only when the polar magnetism of the'respective cores is opposed; in other words, when such poles follow in sequence, and no such opposition is encountered in the bars or back straps that bridge the cores of the coils, the armature is not attracted. This is the condition represented in Fig. 6. Then, however, such sequence is disturbed by a reversal of the poles of either coil, an opposing magnetic field is developed, with the result that the armature is attracted. This condition of affairs is diagramamtically represented in Fig. 7.

In the second form of relay illustrated in Figs. 8, 9 and 10 the modification consists in the substitution for one of the electromagnets a or a of a permanent magnet a, the poles of which of course remain unchanged. The actuation of the armature will here still depend upon the development Patented Aug.1'7, ram.

of an opposing magnetic flux in the bars a that bridge the cores, such result following a flow of current through the electro-magnet, so as to develop poles not in sequence with those of the permanent magnet. The only difference, in brief, between the two constructions of the relay, lies in the fact that with the first form the sequence. may be broken by a change of current in either of the two magnets instead of only one, thus increasing the possibilities of varying the relays action. It is obvious that in this improved relay the connection of the two cores a a of the magnet coils a, al by the bars or back straps a a provides for a closed magnetic circuit through the magnet bars and coils independently of the relay armature (4 whereby this closed circuit assures that under conditions represented in Fig. 6, there is a most free path for the magnetic flux from one magnet core to the other along the opposing bars a which lessens the attraction of the magnets for the independent armature a and in fact prevents its attraction when there is no properly opposed polarity in the magnet bars and cores. 7

In each of the two arrangements of signal circuit illustrated in Figs. 1 and 2 respectively, the use of relays constructed in accordance with the foregoing description is involved, the only differences between the two arrangements thus illustrated, consisting in the use of different forms of signals and a variation in the manner in which the coils are connected in said arrangements, respectively, all of which will be pointed out in what follows. In Fig. 1, then, the signal B is of the upper quadrant, single blade type, there being three such signals and a corresponding number of blocks represented in such figure. Associated with each signal, is a pole changer B operated by the signal in the usual manner to maintain, in connection with a track battery 6, a difference in potential between the two rails b of the preceding block, such that when the signal is actuated, current will flow in one direction or the other through the rails of the tracksection included in said block, and also through the relay A which, as has been indicated, is constructed in accordance with the first construction hereinbefore described. Relay A is, however, in effect a compound relay, being composed, in the present instance, of two relays A of the type shown in Figs. 3, I and 5. The two coils or electro-magnets a designed to be energized by the current through the track circuit are series connected, as shown. However, while only half as many ampere turns for given current are thus obtained, as were there two coils of the same kind arranged as in the ordinary horseshoe magnet, the deficiency is made up by the compensating effect of the nected in series in a shunt circuit 0 off the main or signal actuating circuit C. The compound relay will hence be seen to be made up of two relays, each comprising a pair of coils in closed magnetic circuit. The armatures of such pairs of coils, here designated by numerals 1 and 2, are respectively arranged to open the main circuit C through contact points '0 0 while upon proper energization of the corresponding coils said armatures are adapted to close said main circuit through contact points 0 c or 0 0, respectively. Depending upon how the circuit C is thus closed, various actuation of the corresponding signal will follow. The manner of such actuation may be thus explained, having reference to the same Fig. 1 wherein it will be noted a train I) is represented as bridging the track in block No. 1 at the extreme left: The eifect of such bridging is to shunt the current from the battery (not shown) that is connected with the block in question so as to leave the lefthand coils in the corresponding compound relay A deenergized. The magnetic circuits set up by the other coils in such relay are hence unopposed or in any way affected, and as a result there is no actuation of either armature 1 or 2, so that the main circuit is left open, and the signal B will accordingly stand at danger, as shown. In the case of block No. 2, there will be a current flowing through the two left hand coils in the direction indicated, and as a result an, opposing magnetic circuit set up in the coils of the uppermost pair. The corresponding armature is accordingly raised, with the result that current in the main or actuating circuit is caused to flow therethrough in a proper direction to cause signal B to assume the caution V osition. In the remaining or third block N0. 3), current is also flowing through the two left-hand coils of the compound relay. Such flow, however, is in a direction opposite to that in the preceding block by reason of the shifting of the polechanging device B incidental to the actuation of the signal for such preceding block. Accordingly, itis the lower pair of coils of the compound relay A that now oppose each other, and the corresponding armature that is raised, and by reason of the circuit connections the current is caused to pass to the signal actuating mechanism so as to cause .the signal to assume the clear position.

The same arrangement of relay may be utilized as a repeater, and one thus installedis shown in connection with the second block between relays Nos. 1 and 2.v The disposition of coils in such relay and the manner in which the current of the relay circuit proper passes therethrough, is of course the same as though such relay were employed to control a signal circuit in place of simply the supplementary battery 13 and the circuit including the remaining section of track in the block.

The arrangement of apparatus constituting the modified form of our system illus trated in Fig. 2, will not require detailed explanation, in view of that given above regarding the first arrangement. As has been indicated we here show a two-position signal, that is a two-blade, home and distant, lower quadrant type of signal B. Moreover, the left-hand coils a of the co pound relay are connected in multiple, so that a multiplying effect is here secured in combination with the independently energizedelectro-magnets a, more current flowing through such left-hand coils on account of reduced resistance than in the preceding case where said coils were connected in series. By adjusting the permanently energized coils a up to the maximum of these left-hand coils, we accordingly get twice, or nearly twice, as great an effective pull as would otherwise be secured. In other words, the arrangement in hand multiplies the pull of the left-hand coils, whereas in the other arrangement, the loss incidental to their being connected in series is merely compensated.

'With either arrangement of coils, however, it will be seen that while such coils are separately energized, the maximum magnetic power is obtained when the opposing magnets are equally saturated. By the relative disposition of the permanently energized coils with respect to those paired therewith, and included in the relay circuit proper, it will be seen that the armature of the relay will be attracted only when the pole magnetism of the respective coils opposes each other. As a result of our improved arrangement of relay, there is absolutely no possibility of wrong indication, while the efliciency of the relay, or in other words, its responsiveness to weak currents, is materially increased; and especiallyby the multiplying effect obtainable in the second arrangement ofthe coils we are enabled to get a powerful action or pull on the armature, despite any weakness of current in the original track circuit. Furthermore, and quite important, the system, it will be observed, is practically a wireless one; no circuits, in other words, are required to parallel the lines of the rails, and the only wiring is that involved in connecting up the relay and signals with the adjacent track.

The safety feature of our system arises from the fact that the secondary control is dependent on proper action of the armatures. Any sticking, or other interference, occurring in the free operation of the latter can by no mischance give rise to a false in dication of safety. In terms of the strucuse with other types of signals is merely a matter of simple adaptation. So too, it will be understood that instead of energizing the electro-magnets a by including them in a shunt from the main, or signal, circuit, they may be energized by a current from any fixed source of electrical energy.

Other modes of applying the principle of our invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, pr vided the means stated by any of the following claims or the equivalent of such stated means be employed.

We therefore particularly point out and distinctly claim as our invention 1. In a railway signal system, the combination with a series of successive insulated track block sections, of a signal for each block, a series of track circuits substantially co-extensive with said blocks and inclut ing a pole changer for each block operable by the signal for the block ahead, local circuits including energy sources operating the respective signals, and means controlling said local circuits comprising a relay including two magnets, means connecting said magnets in closed magnetic circuit, and an arma' ture attractable toward said magnet connecting means; one of said magnets being connected in the track circuit of the block ahead of each signal and the other magnet being permanently connected to a source of energy.

2. In a railway signal system, the combination with a series of successive insulated track block sections, of a signal for each block, a series of track circuits substantially co-extensive with said blocks and including a pole changer for each block operable by the signal for the block ahead, local circuits including energy sources operating the respective signals, and means controlling said local circuits comprising a relay including two magnets each having a core, a surrounding coil and two opposing bars bridging opposite ends of the two magnet cores and providing for a closed magnetic circuit through both bars and both cores, and an armature attractable toward one of said core connecting bars; one of said magnets being connected in the track circuit of the block ahead of each signal and the other of said magnets being permanently connected to a source of energy.

F a pole changer for 3. In a railway signal system, the combination with a seriesv of successive insulated track block sections, of a signal for each block, a series of track circuits substantially co-extensive with said blocks and including a pole changer for eachblock operable by the signal for the block ahead, local circuits including energy sources operating the respective signals, and means controlling said local circuits comprising a relay including two pairs of magnets each pair comprising two cores and coils, means connecting the two cores in closed magnetic circuit, and an armature attractable toward said core connecting means; one magnet coil of each pair being connected in the track circuit of the block ahead of each signal and the other magnet coil of each pair being permanently connected to a source of energy.

4. In a railway signal system, the combination with a series of successive insulated track block sections, of a signal for each block, a series of track circuits substantially co-extensive with said blocks and including each block operable by the signal for the block ahead, local circuits including energy sources operating the respective signals, and means controlling said local circuits comprising a relay including two pairs of magnets each pair comprising two cores and coils and two opposing bars bridging opposite ends of the two magnet cores and providing for a closed magnetic circuit through both bars and both cores, and an armature attractable toward'one of said core connecting bars; one magnet coil of each pair being connected in the track circuit of the block ahead of each signal and the other magnet coil of each pair being permanently connected to a source of energy.

5. In a railway signal system, the combination with a series or successive insulated track block sections, of a signal for each block, a series of track circuits substantially co-extensive with said blocks and including a pole changer for each block operable by the signal for the block ahead, local circuits including energy sources operating the re- SP6Cl3i\' 'G slgnals, and means controlling sald local circuits comprising a relay including two pairs ofmagnets each pair comprising two cores and coils, means connecting the two cores in closed magnetic circuit, and an armature attractable toward said core connecting means; one magnet coil or" each pair being connected in multiple in the track circuit of the block ahead of each signal and the other magnet coil of each pair being permanently connected to a source of energy. v

6. In a signal system, the combination 0]": a track divided into a series of blocks; a signal at the entrance of each block, a bat tery and pole changing device at the end of each block, each such device being operable by the adjacent signal; a main circuit and battery for actuating each signal; and a relay adapted to control said main circuit, said relay including two electro-magnets in closed magnetic circuit, one of said electromagnets being connected across therails at the entrance of the blocks at which the signal controlled by said relay is located, and the other electro-magnet being in a shunt from said main circuit.

7. In a signal system, the combination of a track divided into a series of blocks; a signal at the entrance of each block, a battery and pole changing device at the end of each block, each such device being operable by the adjacent signal; a main circuit and battery for actuating each signal; and a relay adapted to control said main circuit, said in closed magnetic circuit respectively, one electro-magnet of each pair being connected across the, rails at the entrance of the block at which the signal controlled by said relay is located, and the other electro-inagnet being connected in a shunt from said main circuit.

Signed by us this 30th day of April, 1910.

JOHN P. BUCHANAN. FREDERICK B. W'IEGAND. Attested by- 1 ANNA L. GILL,

JNo. F. OBERLIN.

Copies of this patent may be obtained for five cents each, .by'addressing the Commissioner of Patents,

Washington, D. G.

relay including two pairs of electro-magnets 

